BACKGROUND: No published studies have compared the effectiveness of
several treatments proposed to reduce cat allergenicity. Cat washing studies
demonstrating efficacy involved very small sample sizes or infrequent washings.
Allerpet-C (Allerpet, Inc., New York, N.Y.) is a widely advertised topical
spray, and acepromazine, a tranquilizer advocated as efficacious in subsedating
doses, have never been scientifically studied.OBJECTIVE: We compared the effects of cat washing, Allerpet-C spray, and
acepromazine with that of no treatment on the shedding of the primary cat
allergen, Felis domesticus 1 by cats.METHODS: In a blinded, comparative, controlled study, we measured the amounts
of Fel d 1 shed during an 8-week treatment period with a sample of 24 female mongrel
cats randomly assigned to four groups; one group received weekly distilled water
washings, one received weekly Allerpet-C spray applications, one received daily oral
acepromazine, and one had no treatment (control). Thirty-minute twice-weekly air
samples were collected from each cat with a laminated plastic-acrylic chamber and
air sampler.RESULTS: One-sample, two-sided t tests comparing baseline to final-week
measurements revealed no significant change in Fel d 1 within each group (mean
change +/- SD: washing; 487.6 +/- 1896.4 mU per 30 minutes, p=0.63; Allerpet-C
spray, 429.2 +/- 871.6 mU per 30 minutes, p=0.46 acepromazine; 620.6 +/- 1031.2,
p=0.52 per 30 minutes). Furthermore, analysis of covariance revealed no significant
change in Fel d 1 levels between groups (p=0.72).CONCLUSIONS: Our data do not show significant reductions in Fel d 1 shedding
as a result of any of these treatments. Therefore we cannot recommend them to
patients allergic to cats.

Evaluation of different techniques for washing cats: quantitation of allergen
removed from the cat and the effect on airborne Fel d 1

BACKGROUND: The purpose of this study was to examine the quantity and
distribution of the major cat allergen, Fel d 1, on cats and to evaluate the efficacy
of washing, both in removing allergen from the cat and reducing airborne allergen levels.METHODS: Airborne samples were collected on four glass fiber filters in a 30
m3 room, before and 3 hours after serial washing of eight cats (45-minute
sampling at 18 L/min for each filter). Aliquots of hair and bath water were also
collected and assayed for Fel d 1 content.RESULTS: Extracting cat hair with tap water or pet shampoo for 3 minutes
removed mean levels of 191 and 245 microg of Fel d 1 per gram of hair, respectively;
the quantity of allergen on samples of cat hair ranged from 1 microg/gm to more than
1770 microg/gm. The highest concentration of allergen was found on hair from the
neck. Estimates of the total Fel d 1 on the cat, based on shaving the whole cat,
ranged from 3 to 142 mg (mean = 67 mg). Washing cats reduced airborne allergen 3
hours later. Washing three cats at weekly intervals for 5 weeks in a veterinarian's
office produced a mean decrease of 44% in airborne Fel d 1 (n=15, p<0.02).
Washing three cats by immersion for 3 minutes at weekly intervals for a 1-month
period produced a mean decrease in airborne allergen levels of 79% (n=12, p<0.001).
However, after repeated washing, the airborne levels before the next wash were not
consistently decreased. The quantity of Fel d 1 removed by immersion varied from 1
to 35 mg. CONCLUSIONS: Cats carry large quantities of Fel d 1, only a small proportion
of which (approximately 0.002%/hr) becomes airborne. Washing cats by immersion
will remove significant allergen from the cat and can reduce the quantity of Fel d 1
becoming airborne. However, the decrease is not maintained at 1 week.

Washing the dog reduces dog allergen levels, but the dog needs to be
washed twice a week.

BACKGROUND: Many asthmatic patients allergic to dogs refuse to part with
their dog, and it is essential to develop techniques for lowering exposure with a
dog in the home.OBJECTIVE: This study investigated the effect of dog washing on the subsequent
recovery of Can f 1 from dog hair clippings and on the airborne allergen over a 7-day
period.METHODS: Dogs, which had not been washed for at least the previous 3 weeks,
were washed with a hand-held shower and proprietary shampoo. Hair clippings and dander
samples from 25 dogs were collected before and immediately after washing. After these
initial studies, 16 dogs had a small tuft of hair clipped from the collar or spinal
area before washing and then daily for the next 7 days. Air sampling was performed in
5 homes, and the air samples were collected (airflow rate, 9 L/min) over an 8-hour
period per day on 10 consecutive days (3 days of baseline sampling before washing
and then 7 consecutive days after washing). Can f 1 level was measured by using 2-site
ELISA.RESULTS: Washing significantly reduced recoverable Can f 1 from clippings (84%
reduction: from 73 microg/g to 12 microg/g [geometric mean]; P<.0001) and from dander
samples (86% reduction: from 347 microg/g to 50 microg/g [geometric mean]; P<.0001).
There was a significant reduction in Can f 1 levels in dog hair over the observed 8-day
period (F=18.4, P<.0001). By using a multiple comparison test, this observed
significance was found to be due to the difference between the baseline levels and
those on days 1 and 2 after washing, with no difference in the baseline Can f 1
compared with days 3 to 7. Airborne Can f 1 levels showed a downward trend, which
reached statistical significance when the data were grouped into 3 sampling periods
as follows: baseline (ie, mean of 3 days before sampling) was compared with days 1 to
4 after washing (41% reduction, 95% Cl 13%-60%) and days 5 to 7 after washing (61%
reduction, 95% Cl 2%-84%; P=.014).CONCLUSIONS: Washing the dog reduces recoverable allergen from dog hair and
dander. The dog needs to be washed at least twice a week to maintain the reduction
in recoverable Can f 1 from its hair. Washing the dog achieves a modest reduction
in the level of airborne Can f 1 in homes with a dog.